1. Field of the Invention
This invention relates to and has among its objects the provision of a novel method for treatment of fibers with ozone-steam mixtures. It is a particular object of the invention to provide a novel method for treating proteinous animal fibers with ozone-steam mixtures in order to shrinkproof them. Further objects of the invention will be evident from the following description wherein parts and percentages are by weight unless otherwise specified.
2. Description of the Prior Art
A process for treating animal fibers with gaseous ozone and steam is described in U.S. Pat. No. 3,149,906 (hereinafter referred to as '906). A stream of ozone and steam is blown through the textile under treatment in the '906 process.
A disadvantage of the known process is that ozone is not used efficiently and losses of 80-85% of ozone usually occur. Inefficient use of ozone is costly because large amounts of energy are expended to both produce the ozone and to destroy the unused gas. Furthermore, larger ozone generators are required when excess amounts of ozone must be prepared and such large generators are expensive.
Closed chambers for treating food material with steam are known. In U.S. Pat. No. 3,982,481 a food product is passed into a chamber which is sealed to prevent escape of steam.
The product enters the chamber first through water and then through a combination of a paddle wheel and flap, all of which maintain the chamber steam-tight. For removal of the product from the chamber, the above sequence is reversed. Sealed steam chambers are cumbersome to use and impractical for uses other than as a blanching apparatus for food material.
A hump-back tunnel blancher is described in "Misc. Publication 540," U.S. Department of Agriculture, p. 40 (1944). The center of the tunnel is located at a higher elevation than either the entrance or discharge ends. Steam is maintained in the tunnel center to the exclusion of air by the difference in density between steam and air at ordinary temperatures, by the use of curtains, and by positioning the steam jets so as to neutralize the kinetic energy of the jets.